Sorry it took me a little bit to post pics of my pull down. The Artillerie Inrichtingen brass as you can see from my second photo marked their projectiles on the base as well.

Studying the cartridge more I have discovered a change in head stamping circa 1921. Pre 1921 you will see codes at only 12 and 6 o'clock. Post 1921 you will possibly have markings now at roughly 12, 3, 6, and 9 o'clock. Marks at 12 o'clock denote year of manufacture, 6 o'clock indicates brass supplier/manufacture, 3 o'clock is date of manufacture, and 9 o'clock is powder lot. Many of the cases were re used and subsequently over stamped at later dates. This could explain the headstamp with all numbers we were having difficulty Identifying. Re used cases were either over stamped with new numbers, a O, or in some cases a triangle.

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